Yes last I heard or read was latest is turning it into a shopping mall but seeing as Detroit is in financial strife can't see that happening.
The Packard plant site is a 40 acre site quite close to the center of Detroit. Its one of those places that people from outside detroit think they can make money due to the proximity of the plant to downtown.
only trouble is that this area of town is still pretty rough. A big factor in that is because of a crumbling set of factory buildings that are used for illegal dumping, drug deals etc. It's a pretty rough location and not somewhere that most people who live in Detroit would go very near. I lived in Detroit for four years and even with an interest in cars, I never went there. There are better ruins to go and see that are safer and easier to get to.
Instead of a shopping mall, some parts of the site may get re-vitalized for other purposes but you would need to spend millions to clean up the entire site to get people to go near it, especially after dark. Like other urban renewal projects, the site is polluted from its time as a working factory, but also as a dumping ground.
Another thing to note is that this an older style factory complex with many separate buildings rather than one big one. Compared to say a model T ford, Packards were largely hand built as befitting and automobile of that stature. There is a bridge over grand blvd where they used to send the cars back in the day. I know when I lived there there was fear of its collapse as scrappers had taken some of the metal from it.
There is a guy from Peru who is the latest person who is having a go. My bet is the Packard plant will break him as it has broken others before him. I think he paid about USD$450k for the entire site.
I do wish him luck. The city of Detroit has a character that many cities lack and I would like to see projects like this succeed.